Wow. This has been a little difficult.
I'm sure the time difference hasn't helped but initially it seemed like I really had to press people and send multiple e-mails in order to get my questions answered!
Unlike my previous experiences with EdRobinsonsDiveAdventures or Extended Horizons in Maui where I was able to book almost immediately, this has taken a couple of weeks. Actually, one place took over 2 weeks to respond to my e-mails!
Vietnam has not been known as a dive destination in the past but the industry seems to be steadily growing in Nha Trang.
With the initiation of the Hon Mun Marine Protected Area in 2001, diving seems to have become more attractive to locals and tourists alike.
As with many other countries in SE Asia, uncontrolled fishing practices have destroyed a lot of the sea life but in the MPA, coral and other flora/fauna have been able to grow and develop.
"The Nha Trang Bay MPA is about 13,000 hectares and comprises many important habitats including coral reefs, seagrass and mangrove areas. Nha Trang Bay houses the highest coral reef diversity of any surveyed location in Vietnam. Due to its biodiversity values, Nha Trang Bay is an “area of highest national priority” for marine conservation and coastal tourism."So I have to do a little bit of research to figure out where I'm going and even though Nha Trang is the major city, it's not actually where I'm staying. The map I posted here I found online on some resort's website however it's just about where I'm staying (Ninh Van). Mun Island is where most of the divers go.
After hitting some online forums to get some information on the local diving, I wrote to a handful of dive operators - the ones that had the best reviews on Tripadvisor. I also contacted the Six Senses Resort about their offerings and they explained that they do work with a local dive operator (that maintains a "shop" at the resort) and sent me a pricelist. I immediately balked at the $200 2-tank dive price.
I eventually contacted Sailing Club divers and learned that they're the operator that the resort works with and instead of sending me a pricelist for dives leaving out of Nha Trang, I once again got the price-list featuring the 4,000,000 VND 2-tank dives ($200 US approx). I was also told that 3-tank dives aren't offered because of the hours of the Marine Protected Area - apparently the boat at the resort leaves later than boats from the city. They meet up with regular boat operations already in progress. I'd rather get up early and get in 3 tanks! Oh and I was also told that I could just pop over to get these dives scheduled. (There's a dedicated staff at the resort). I guess I'm used to planning things in advance because there's just less disappointment that way.
Also, in my initial e-mails to operators I do explain that I am a certified diver that isn't interested in taking an open water PADI course. They keep trying to push the courses! My buddy is certified as well (however still a novice) but he had taken a refresher a couple of weeks ago.
I've been asking which areas are suitable for a new diver and current water temps and suggestions about gear, etc. I also mention that getting 3-tank dive days is important for me because I want to take advantage of my time there!
Each time it's like pulling teeth. For ever 10 questions, I might get answers to 2 or 3. I seriously started to wonder if these places really want my business.
I learned about a place up north about 2.5 hours called Whale Island from the Rainbow Divers website which is a remote and nice area as well but according to one person I contacted the whale sharks that used to be in the area aren't really out there any more. My initial excitement about planning that excursion has passed. This might be a good thing because it'd be $100 for the journey up there via road, otherwise a $600 speedboat ride - either way it also required a super early AM wake up time. It's not totally out though, there are afternoon/evening shore dives offered.
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So far I've primarily been in contact with Rainbow Divers and it looks like they're the company that's going to be taking my money.
Finally getting dives sorted out. I wanted to try out a couple of operators but I guess it's going to be RD since they're are the only ones that seem to be actively responding in the most timely manner. The time difference also makes things a bit more of a hassle.

Apparently Whale Island no longer lives up to the hype so the 26th I'm going to take a private speedboat to the Electric Nose dive sites even though another operator told me that I'd probably not enjoy it due to the dynamite fishing. Yeah, I suppose whale song is a better soundtrack to dive to but I'll just have to live with the fact that it's not going to happen EVERY time I get underwater... Speedboat is gonna cost me $300. 3-tanks is going to be just under $100. I get picked up at the resort.

The 27th I'll be diving with Richard at the Hon Mun Marine Protected Area - a variety of nice and easier sites for 3 more relaxing dives! Thought it'll most likely be on one of those nice n full boats with a bunch of other people. We'll get a $30 transfer into the city to get our paperwork and gear sorted out, and then we head out! Afterwords, there's a bar attached to the dive shop. I think that's where we'll be!
There are other activities in Nha Trang but I'm so very tempted to book a third day of diving... !!!
We'll just have to see how things progress!